Ball pump



y 8, 1965 R. E. RAYMOND 3,183,850

BALL PUMP Filed May 10, 1962 6 Sheets-Sheet l FIG-l INV EN TOR.

ROBERT E. RAYMOND BY ATTORNEYS May 18, 1965 Filed May 10, 1962 R. E. RAYMOND BALL PUMP 6 Sheets-Sheet 2 INV EN TOR.

ROBERT E. RAYMOND AT ORNEYS y 18, 1965 R. EQ RAYMOND 3,183,850

BALL PUMP Filed May 10, 1962 6 Sheets-Sheet 3 N v1- N Q N m & m w W Qs w s Q w I R k? I u u-n I la INVENTOR.

ROBERT E RAYMOND ATTORNEYS May 18, 1965 R. E. RAYM'OND 3,183,850

BALL PUMP Filed May 10, 1962 6 Sheets-Sheet 4 FIG-7 INVEN TOR.

ROBERT E. RAYMOND AT TbRNEYs BALL PUMP Filed May 10, 1962 6 Sheets-Sheet 6 FIG-9 IN V EN TOR.

ROBERT E. RAYMOND ATTORNEYS United States Patent 3,183,359 BALL PUMP Robert E. Raymond, 131 Norcross Road, Zanesvilie, Ohio Filed May 10, 1962, Ser. No. 187,369 19 Claims. (Cl. 103-174) This invention relates to hydraulic machines such as pumps, fluid motors, and the like.

In general, as one aspect of the present invention the apparatus comprises an improved ball piston type pump that incorporates a plurality of balls mounted for reciprocating movement in a plurality of cylinders in such a manner that the balls serve the dual function of piston means for the cylinders and bearing members that engage the eccentric that reciprocates the pistons in the cylinders.

The pump further comprises, in one of its aspects, a novel spring return mechanism that includes a piston return apparatus that does not detract significantly from the displacement or reduce the compression ratio of the pump.

As another aspect of the present invention the pump includes a novel piston return apparatus thatpermits the balls pistons to rotate on the eccentrics that drive them.

As another aspect of the present invention the pump includes a novel spring type piston return apparatus which permits control of the spring rate since the spring is located exterior of the cylinder chamber. This feature is fundamental to delivering high forces with controlled stresses.

As another aspect of the present invention the pump can .be provided with a novel magnetic piston return apparatus for maintaining the ball type pistons biased towards the eccentric that reciprocates the pump in their cylinders.

As another aspect of the present invention the pump comprises a novel intake valving arrangement for use with the ball piston principle. This comprises the providing of inwardly facing open-ended slots in the base of the cylinder walls which form intake valve ports. This construction permits the lobe of the driving eccentric to move through the intake slots and movement of the major diameter axes of the ball pistons beyond the thresholds of the slots and yet the ball pistons are effectively retained in the cylinders. Moreover, this construction permits larger intake port areas to be developed even though the main pressure stroke is less than half the diameter of the ball pistons.

As another aspect of the present invention, the ball pistons, being of curved configuration, inherently provide controlled pregressive closing of the intake ports notwithstanding the fact that the eccentric is moving at a finite velocity on the power stroke. This provides a cushioned or throttled closing of the intake ports which is important in maintaining low noise levels.

In view of the above described aspects it will be understood that the pump of the present invention uniquely incorporates a ball-type piston in a manner whereby the ball serves the triple function of a piston means for its cylinder, a bearing member on the driving eccentric, and a valve element for the intake valve port. By utilizing a ball to accomplish all three of these functions in a simple manner, the basic cost of the pumping mechanism is greatly reduced.

As another aspect of the present invention the pump can be readily provided with variable displacement features. This is readily accomplished by varying the pressure of the oil in the crank case of the pump whereby the return stroke of the piston, towards the eccentric, is hydraulically limited. This type of hydraulic variable displacement control is applicable to the previously described modification of the pump that incorporates the mechanical spring type piston return apparatus.

In the modification of the pump that incorporates a magnetic field for returning the ball pistons to the eccentric the variable displacement feature can be easily incorporated by varying the intensity of the magnetic field that biases the ball pistons towards the eccentric that drives them.

As another aspect of the present invention the previously described piston return apparatus can be incorporated in fluid motors with the addition of timed ported valving in place of the low cost ball check valving incorporated in the pump structures. In the ball type fluid motor modification the basic cost savings results from the ball serving the dual function of a piston and bearing means.

As another aspect of the present invention, the previously described pump incorporates the important feature of being adaptable for the addition of additional ball pistons to a standard pump frame. For example, if the basic pump frame incorporates eight cylinders, it is possible to use anywhere from one to eight ball pistons without any changes other than the inserting of the ball piston and outlet check valves, the latter being carried in a removable and piston return cartridge. With this arrangement pistons can be removed or added in the field to permit changing of the capacity or characteristics of the pump. In addition to this, standard pumps can be sold using standard pump frames that have gone through production boring for any selected standard number of cylinders. From these basic frames pumps can be assembled with, for example, two, four, eight of more piston arrangements and have balanced flow characteristics.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred form of embodiment of the invention is clearly shown.

In the drawings:

.FIG. 1 is a side sectional View of a radial piston pump constructed in accordance with the present invention, the section being taken along the line 11 of FIG. 2;

FIG. 2 is a front sectional view of the pump of FIG. I, the section being taken along the line 2-2 of FIG. 1;

FIG. 3 is a partial sectional view showing an intake port construction for the pump of FIG. 1, the section being .taken along the line 3-3 of FIG. 2;

FIG. 4 is a second sectional view of the intake port construction for the pump of FIG. 1, the section being taken along the line 4-4 of FIG. 1;

FIG. 5 is an enlarged partial sectional view of a piston return apparatus of the pump of FIG. 1, the section being taken along the line 55 of FIG. 2;

FIG. 6 is a partial sectional view of a modified piston return apparatus constructed in accordance with the present invention;

FIG. 7 is a side sectional view of an axial piston pump constructed in accordance with the present invention, the section being taken along the line 7-7 of FIG. 8;

FIG. 8 is an end sectional view of the pump of FIG. 7, the section being taken along the line 88 of FIG. 7; and

FIG. 9 is a partial sectional view of a radial piston type pump provided with a magnetic piston return means and constructed in accordance with the present invention, the section being taken along a vertical plane through the center line of the pump.

Referring in detail to the drawings, FIG. 1 illustrates a radial piston type pump constructed in accordance with the present invention which comprises a casing means indicated generally at 20, said casing means including a cylinder block portion 22 that is joined to end plates 24 and 26 at annular seals 28 and 30.

As is best seen in FIG. 1 cylinder block 22 comprises two radially disposed cylinders 42 and 4-4 in which are mounted balls 46 and 48 which form the pumping pistons for the apparatus.

Balls 46 and 48 are reciprocated in cylinders 42 and 44 by an eccentric 50 secured to a drive shaft 52 by a key 54. Drive shaft 52 is rotatably mounted on end plates 24 land 26 by the roller bearings 56 and 58 and a resilient oil seal 60 is provided between drive shaft 52 and end plate 56.

Low pressure oil is supplied to cylinders 42 and 44 via an intake passage 62 in mounting plate 32 and cylinder block 22, the crank case of the pump 64, and the intake slots 66 which communicates with the interior of cylinder 42 and 44 when the ball pistons 46 and 48 are at the lower regions of their strokes. The intake flow of oil from crank case 64 through intake slots 66 is illustrated at the arrows in FIGS. 3 and 4.

As is best seen in FIG. 5, the ball pistons 46 and 48 are constantly biased towards eccentric 51 by a compression spring 70 interposed between spring mounting members 72 and 74, the latter being mounted on the upper end of a piston return rod 76 that slidably is guided in a hole '78 formed through outlet valve element 80.

With continued reference to FIG. 5, outlet valve element 80 is constantly biased towards an outlet valve seat 82 by a compression spring 84 interposed between outlet valve member 80 and spring mounting member '72.

With continued reference to FIG. 5, threaded plug 86 is nemovably mounted in a threaded hole 88 and provides means for removably mounting the outlet valve element and spring return apparatus in the casing means 26. A resilient seal 92 is provided at the junction of plug 86 with casing means 20. With reference to FIG. 2 pressurized oil is discharged from cylinder 44 via valve chamber 94, passages 96, 98, and 160 and outlet port 102 leading to the load.

. Since passages 96 and 98 are formed by drilling holes in cylinder block portion 22 the plugs 106 serve to close the ends of the drilled passages.

Oil from the upper cylinder 42 is delivered to outlet port 102 via passages 98 and 108. Passage 98 includes an upper end that communicates with the upper cylinder 42 by a horizontal passage, not illustrated, identical to the passage 96 seen in FIG. 2.

In operation of the pump of FIGS. 1-6, shaft 52 is driven by a prime mover whereby the lobe 108 on the eccentric 50 reciprocates ball pistons 46 and 48 in their respective cylinders. When one of the balls is at the lower region of its stroke, outlet valve 80 is closed by valve return spring 84 whereby the suction created in cylinder 44 draws low pressure oil from crank case 64 through inlet port slots 66. Upon continued rotation of eccentric 50 ball 46 or 48 is driven radially outwardly whereby intake port slot 66 is closed when the major diameter axis 110 of the ball passes the threshold edges 112 of intake port slot 66. See FIGS. 3-5. Upon closing of the intake port slot the pressurized oil opens outlet valve element 80 whereby oil is driven outwardly to the load in the previously described manner.

Reference is next made to FIGS. 7 and 8 which illustrates an axial piston type pump constructed in accordance with the present invention which includes a casing means indicated generally at 120 that comprises a front casing portion 122 and rear casing portion 124 said casing portions being joined together at confronting surfaces 126 and 128 by a plurality of studs 130.

With continued reference to FIGS. 7 and 8, a drive shaft 132 is rotatably supported in front casing portion 122 by a bearing 134 and a resilient seal 136 is provided between the drive shaft and the casing means.

The axial piston pump of FIGS. 7 and 8 includes a plurality of ball pistons 140 mounted for reciprocating movement in a plurality of axially disposed cylinders 142.

An eccentric indicated generally at 144 is mounted on drive shaft 132 by a nut 146 and key 148 and the ball pistons roll on an eccentric ring 150.

The outlet valve apparatus and piston return apparatus of the pump of FIGS. 7 and 8 is identical to that previously described in connection with the radial type of FIGS. 1 and 2 and the various elements of these apparatus are illustrated in enlarged detail in FIG. 5. The outlet valve elements of FIGS. 7 and 8 that are identical to corresponding elements in the pump of FIGS. l5 are designated by identical numerals.

Low pnessu-re oil enters a crank case 154 of the pump of FIGS. 7 and 8 via an intake port 156 and the oil enters the cylinders 142 via intake port slots 66 that include threshold edges 112, FIGS. 3-5, said intake port slots 66 being closed when the major diameter axes 110 of the balls pass the threshold edges 112 of the intake port slots.

It should be pointed out that the previously mentioned eccentric ring includes a high portion 160 that extends into intake port slot 66. This unique construction permits the balls to move to the bottom of their strokes, to positions wherein the major diameter axes 110 are below the edges 112, with the balls being still retained in their respective cylinder-s by the cylinder side wall portions that lie below the threshold edges 112.

The same important feature is present in the radial pump of FIGS. 1 and 2 wherein the lobe 108 of the eccentric extends into the intake port slot 66.

In the axial pump of FIGS. 7 and 8 eccentric means 144 is rotatably mounted and accurately positioned by a tapered roller bearing assembly indicated generally at 170.

Pressurized oil is delivered from cylinders 142 via valve chambers 94, passages 172, and outlet port 1'74 to the load.

In operation of the pump of FIGS. 7 and 8 when drive shaft 132 is driven by a suitable prime mover eccentric ring 150 reciprocates ball pistons 140 in their respective cylinders and each time a major diameter axis of a ball drops below a threshold edge 112 of a respective intake port slot then oil is drawn from crank case 154 into the cylinder. As eccentric ring 150 continued to rotate the high portion 168 drives the ball upwardly in its cylinder and when the major diameter axis 110 of the ball passes threshold edge 112 pressurized oil in cylinder 142 opens outlet valve element 80 whereby pressurized oil is discharged to the load via a passage 172 leading to outlet port 174.

Reference is next made to FIG. 9 which illustrates a portion of a modified radial piston pump provided with magnetic piston return apparatus. This pump includes a casing means indicated generally at that forms a plurality of radially extending cylinders one of which is indicated generally at 182. Each of the cylinders carries a ball piston 140 that is reciprocated by rotation of an eccentric indicated generally at 184, the latter being mounted on a drive shaft 186.

Ball piston 140 is constantly biased towards eccentric 184 by a magnetic field diagrammatically illustrated by the closed circuit lines of force 188. These lines of force are generated by the coil 19!) which includes leads 192 and 194 that are connected to a source of electrical energy not illustrated.

Housing means 189, drive shaft 186, and an eccentric means 184 are formed of ferrous metal to provide a high intensity closed loop magnetic field diagrammatically indicated at 188.

The top of cylinder 182 is closed by an inner plug 198 and an outer plug 200 the latter being screwed into threaded hole 202 in the casing means.

A resilient seal 204 is provided between inner and outer plugs 198 and 200 and any leakage that may pass from cylinder 182 between the confronting surfaces of the inner plug 198 and the housing means is delivered to the outlet port 216 via annular passage 206, horizontal passage 208, vertical passage 210, outlet valve chamber 212, and vertical passage 214.

Cylinders 182 receive low pressure oil from crank case 220 via intake slots 66 when the major diameter axes 110 of the balls move below threshold edge 112 of the intake slots.

Each of the cylinders 182 includes an outlet valve element 218 that'isreturned to its seat 228 by a compression spring 222 that is retained in place by a spring mount 224 carried by a removable plug 226.

While the forms of embodiments of the present invention as herein disclosed constitute preferred forms, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow:

I claim:

1. An improved hydraulic machine comprising, in combination, casing means including a cylinder having a cylinder wall provided with a slotted inner end forming a ball guide and an intake port, exhaust valve means for said cylinder; shaft means rotatably mounted in said casing means and including a cam means; a ball disposed in said cylinder in engagement with said cam means and movable to an inner location in said cylinder wherein the major diameter of said ball is disposed inwardly of said intake valve port to open said port, said ball thereby serving the triple function of a piston means for said cylinder, a bearing member on said cam means, and a valve element for said intake valve port; and means biasing said ball towards said eccentric.

2. The hydraulic machine defined in claim 1 wherein said ball is formed of ferrous metal and said biasing means is provided by a magnetic field in which said ball is disposed and wherein said magnetic field is formed by an electrically energized coil surrounding said shaft means.

3. An improved hydraulic machine comprising, in combination, casing means including a cylinder and an outer end portion forming a valve seat for a valve port; shaft means rotatably mounted in said casing means and including a cam; a ball disposed in said cylinder and in engagement with said cam, said ball thereby serving the dual function of a piston means for said cylinder and a bearing member on said cam; a valve member engaging said valve seat and including a bore forming a rod guide; a rod extended through said bore and engaging said ball; and resilient means outside said cylinder for biasing said rod towards said ball and said valve member towards said valve seat.

4. The hydraulic machine defined in claim 1 wherein said ball is formed of ferrous metal and said biasing means is provided by a magnetic field in which said ball is disposed.

5. The hydraulic machine defined in claim 1 wherein said biasing means comprises a rod extended into said cylinder and in engagement with said ball, and resilient means biasing said rod towards said ball.

6. The hydraulic machine defined in claim 1 that comprises an outer end portion on said cylinder forming an annular seat for a valve port; a valve member engaging said seat and including a bore forming a rod guide; a rod extended through said bore and engaging said ball; and resilient means biasing said rod towards said ball and said valve member towards said valve seat.

7. The hydraulic machine defined in claim 1 that includes a plurality of said cylinders and said balls disposed radially of and driven by said cam means.

8. The hydraulic machine defined in claim 1 that includes a plurality of said cylinders and said balls disposed radially of'and driven by said cam means, said biasing means being formed by a magnetic field in which said balls are disposed.

9. The hydraulic machine defined in claim 1 that includes a plurality of said cylinders and said balls disposed radially of and drivenby said cam means, said intake port being formed by an open ended slot, said cam means being movable through said slot.

10. The hydraulic machine defined in claim 1 wherein said cylinder includes a longitudinal axis extending parallel with the axis of rotation of said shaft means.

11. The hydraulic machine defined in claim 1 wherein said cylinder includes a longitudinal axis extending parallel with the axis of rotation of said shaft means, said biasing means being formed by a magnetic field in which said balls are disposed.

12. The hydraulic machine defined in claim 1 wherein said cylinder includes a longitudinal axis extending parallel with the axis of rotation of said shaft means, said intake port being formed by an open ended slot, said cam means being movable through said slot.

13. An improved hydraulic machine comprising, in combination, casing means including a cylinder having a cylinder wall the inner end of which is provided with an open ended slot forming an intake valve port and a ball guide; shaft means rotatably mounted in said casing means and including cam means the outer portion of which moves through said slot; a ball disposed in said cylinder, in engagement with said cam means, and movable to an inner location in said cylinder wherein the major diameter of said ball is disposed inwardly of said intake valve port, said ball thereby serving the triple function of a piston means for said cylinder, a bearing member on said eccentric, and a valve element for said intake valve port and means biasing said ball towards said eccentric.

14. The hydraulic machine defined in claim 13 wherein said ball is formed of ferrous metal and said biasing means is provided by a magnetic field in which said ball is disposed;

15. The hydraulic machine defined in claim 13 wherein said biasing means comprises a rod extending into said cylinder and in engagement with said ball; and resilient means biasing said rod towards said ball.

16. The hydraulic machine defined in claim 13 that comprises an outer end portion on said cylinder forming an annular seat for a valve port; a valve member engaging said seat and including a bore forming a rod guide; a rod extended through said bore and engaging said ball; and resilient means biasing said rod towards said ball and said valve member towards said valve seat.

17. An improved hydraulic machine comprising, in combination, casing means forming a cylinder; an cecentric rotatably mounted in said casing means; a ball including a first side in rolling engagement with said eccentric and a second side forming a hemispherical piston head exposed to the interior of said cylinder; a cylinder head member at one end of said cylinder and including a bore forming a rod guide; a rod extended through said bore; said bore engaging said ball; a spring retainer member overlying said cylinder head member; and spring means mounted between said spring retainer member and the outer end of said rod.

18. An improved hydraulic machine comprising, in combination, casing means formed of ferrous metal and including a cylinder and an annular casing portion, said cylinder including a cylinder wall the inner end of which is provided with an open ended slot forming an intake valve port; flow control valve means for said cylinder; drive shaft means formed of ferrous metal and including a shaft portion extending through said annular casing portion and an eccentric portion located at one end of said cylinder and rotatable through said slot; a coil surrounding said shaft portion and connected with a source of electrical energy; and a piston in said cylinder and in free engagement with said eccentric, said piston being disposed in a magnetic field induced in said drive shaft means .and said annular casing portion :by said coil.

19. An improved hydraulic machine comprising, in

-con1bination, casing means formed of ferrous metal and including a cylinder and an annular casing portion, said cylinder including a cylinder wall the inner end of which is provided Wtih an open ended slot forming an intake valve port; flow control valve means for said cylinder; drive shaft means formed of ferrous metal and including a shaft portion extending through said annular casing portion and an eccentric portion located at one end of said cylinder and rotatable through said slot; a coil surround ing said shaft portion and connected with a source of electrical energy; and a ball including a first side in rolling engagement With said eccentric and a second side forming a hemispherical piston head exposed to the interior of said cylinder, said ball being disposed in a magnetic field induced in said drive shaft means and said annular casing portion by said coil.

References Cited by the Examiner UNITED STATES PATENTS 2,543,796 3/51 McGee 103-174 2,788,748 4/57 Szezepanek 103123 3,016,019 1/62 Rineer 103-123 3,040,665 6/62 Humphrey 103227 FOREIGN PATENTS 532,800 11/56 Canada. 7 602,974 1/ 33 Germany.

852,329 10/ 60 Great Britain.

LAURENCE V. EFNER, Primary Examiner. 

1. AN IMPROVED HYDRAULIC MACHINE COMPRISING, IN COMBINATION, CASING MEANS INCLUDING A CYLINDER HAVING A CYLINDER WALL PROVIDED WITH A SLOTTED INNER END FORMING A BALL GUIDE AND AN INTAKE PORT, EXHAUST VALVE MEANS FOR SAID CYLINDER; SHAFT MEANS ROTATABLY MOUNTED IN SAID CASING MEANS AND INCLUDING A CAM MEANS; A BALL DISPOSED IN SAID CYLINDER IN ENGAGEMENT WITH SAID CAM MEANS AND MOVABLE TO AN INNER LOCATION IN SAID CYLINDER WHEREIN THE MAJOR DIAMETER TO SAID BALL IS DISPOSED INWARDLY OF SAID INTAKE VALVE PORT TO OPEN SAID PORT, SAID BALL THEREBY SERVING THE TRIPLE FUNCTION OF A PISTON MEANS FOR SAID CYLINDER, A BEARING MEMBER ON SAID CAM MEANS, AND A VALVE ELEMENT FOR SAID INTAKE VALVE PORT; AND MEANS BIASING SAID BALL TOWARDS SAID ECCENTRIC. 